Consider this:
URL baseUrl = new URL("file:///C:/temp/");
Pipeline pipeline = new NonCachingPipeline();
pipeline.addComponent(new FileGenerator(new URL(baseUrl, "xyz.xml"));
pipeline.addComponent(new XSLTTransformer(new URL(baseUrl, "xyz.xslt"));
pipeline.addComponent(new XMLSerializer());
pipeline.invoke(new InvocationImpl(System.out));
This simple pipeline has these potentially cacheable components;
xyz.xml, xyz.xslt, the result of the XSLT transformation, and the final
result of the pipeline. As it relates to the pipeline I don't see how
the URL.getLastModified() really helps as it could apply to any of these
items, two of which aren't even URLs.
Ralph
Steven Dolg wrote:
Carsten Ziegeler schrieb:
Steven Dolg wrote:
How about:
URL url = new URL("some url");
UrlConnection connection = url.openConnection();
connection.getLastModified();
Not sure it this really works in all cases, but appears to be quite
suitable and easily extensible.
Yes, this works for many cases, but not for cases like where you have
an expiry date etc. What do you mean by "easily extensible"?
url.openConnection() actually returns a subclass of URLConnection
depending on the protocol of the URL.
So own protocol implementations can return own subclasses that
implement this (and other methods) accordingly.
And - at least theoretically - provide additional methods for handling
specific stuff, e.g. expiration dates.
Carsten
